<template>
  <div class="sidebar">
    <el-menu
            class="sidebar-el-menu"
            :default-active="onRoutes"
            :collapse="collapse"
            background-color="#324157"
            text-color="#bfcbd9"
            active-text-color="#20a0ff"
            unique-opened
            router
    >
      <template v-for="item in items">
        <template v-if="item.subs">
          <el-submenu :index="item.index" :key="item.index">
            <template slot="title">
              <i :class="item.icon"></i>
              <span slot="title">{{ item.title }}</span>
            </template>
            <template v-for="subItem in item.subs">
              <el-submenu
                      v-if="subItem.subs"
                      :index="subItem.index"
                      :key="subItem.index"
              >
                <template slot="title">{{ subItem.title }}</template>
                <el-menu-item
                        v-for="(threeItem,i) in subItem.subs"
                        :key="i"
                        :index="threeItem.index"
                >{{ threeItem.title }}
                </el-menu-item>
              </el-submenu>
              <el-menu-item
                      v-else
                      :index="subItem.index"
                      :key="subItem.index"
              >{{ subItem.title }}
              </el-menu-item>
            </template>
          </el-submenu>
        </template>
        <template v-else>
          <el-menu-item :index="item.index" :key="item.index">
            <i :class="item.icon"></i>
            <span slot="title">{{ item.title }}</span>
          </el-menu-item>
        </template>
      </template>
    </el-menu>
  </div>
</template>

<script>
  import bus from '../common/bus';

  export default {
    data() {
      return {
        collapse: false,
        items: [
            {
                icon: 'el-icon-lx-home',
                index: 'dashboard',
                title: '系统首页'
            },
            {
                icon: 'el-icon-lx-cascades',
                index: 'user',
                title: '用户信息'
            },
            {
                icon: 'el-icon-lx-copy',
                index: 'tabs',
                title: 'tab选项卡'
            },
            {
                icon: 'el-icon-lx-calendar',
                index: '3',
                title: '表单相关',
                subs: [
                    {
                        index: 'form',
                        title: '基本表单'
                    },
                    {
                        index: '3-2',
                        title: '三级菜单',
                        subs: [
                            {
                                index: 'editor',
                                title: '富文本编辑器'
                            },
                            {
                                index: 'markdown',
                                title: 'markdown编辑器'
                            }
                        ]
                    },
                    {
                        index: 'upload',
                        title: '文件上传'
                    }
                ]
            },
            {
                icon: 'el-icon-lx-emoji',
                index: 'icon',
                title: '自定义图标'
            },
            {
                icon: 'el-icon-pie-chart',
                index: 'charts',
                title: 'schart图表'
            },
            {
                icon: 'el-icon-rank',
                index: '6',
                title: '拖拽组件',
                subs: [
                    {
                        index: 'drag',
                        title: '拖拽列表'
                    },
                    {
                        index: 'dialog',
                        title: '拖拽弹框'
                    }
                ]
            },
            {
                icon: 'el-icon-lx-global',
                index: 'i18n',
                title: '国际化功能'
            },
            {
                icon: 'el-icon-lx-warn',
                index: '7',
                title: '错误处理',
                subs: [
                    {
                        index: 'permission',
                        title: '权限测试'
                    },
                    {
                        index: '404',
                        title: '404页面'
                    }
                ]
            },
            {
                icon: 'el-icon-lx-redpacket_fill',
                index: '/donate',
                title: '支持作者'
            },
          {
                icon: 'el-icon-lx-redpacket_fill',
                index: '/table',
                title: '支持作者'
            }
        ]
      };
    },
    computed: {
      onRoutes() {
        return this.$route.path.replace('/', '');
      }
    },
    created() {
      // 通过 Event Bus 进行组件间通信，来折叠侧边栏
      bus.$on('collapse', msg => {
        this.collapse = msg;
        bus.$emit('collapse-content', msg);
      });
    }
  };
</script>

<style scoped>
  .sidebar {
    display: block;
    position: absolute;
    left: 0;
    top: 70px;
    bottom: 0;
    overflow-y: scroll;
  }

  .sidebar::-webkit-scrollbar {
    width: 0;
  }

  .sidebar-el-menu:not(.el-menu--collapse) {
    width: 250px;
  }

  .sidebar > ul {
    height: 100%;
  }
</style>
